196 MARINE AND FRESHWATER FISHES 



popularly known as " Skate-barrows," or " pixie's purses," 

 are among the "commoner objects of the sea-shore," left 

 with the flotsam and jetsam of the ocean when the tide 

 goes down. 



The Sting Ray or Fire- fta.lre(Trygon pas tmaca), No. 225, 

 is remarkable among the Skate tribe from the circumstance 

 that one or two long sharply serrated spines are developed 

 towards the centre of the tail in place of the first dorsal fin. 

 In life, as observed of examples in aquaria, the tail with 

 its spines is elevated above the back after the manner of 

 the tail of a Scorpion, and constitutes a very formidable 



J 



FIG. 31. STING RAY ( Trygon pastinaca}. 



offensive and defensive weapon, with which the fish can 

 deal lacerated, extremely painful, and even dangerous 

 wounds. The spines of certain exotic species are utilised 

 by the natives of Polynesia and various savage tribes as 

 barbs for their arrows, spears, and other weapons. A fine 

 example of the Sting Ray is contained among the spirit- 

 preserved series forming the Day Collection, casts being 

 also on view in the Buckland Museum. A close ally of 

 this type, but a much larger and rarer form is the Eagle 

 Ray (Myliobatis aquila), No. 226, bearing like the last- 

 named species a formidable defensive spine, but having a 



